This proposed research project examines the association of childhood and adolescent affective and anxiety disorders with two specific genetic disorders involving X chromosome abnormalities in females, the fragile X (fra X) and Turner syndromes. The developmental course of affective and anxiety disorder symptoms and their association with social skills development will be investigated in these populations. Reports of increased mood and anxiety disorders among adult women with fra X or Turner syndrome indicate the need to study the presence and clinical features of these disorders in female children with these syndromes. The investigation also provides a compelling opportunity to elucidate the association between genetic factors involving the X chromosome with affective and anxiety disorders in children and adolescents. The specific hypotheses are: 1) Girls with fra X and girls with Turner syndrome will show greater frequency and severity of depression and anxiety disorders than their non-affected, female siblings; 2) The frequency and severity of depression and anxiety disorders will be maintained over time and indicate chronic, intermittent recurrence; 3) There will be a positive correlation between social skills deficits and severity of symptoms of depression and/or anxiety. Furthermore, social skills deficits ratings at initial assessment will be associated with the persistence of depression and anxiety at a follow-up assessment.